Pillar Coral

It’s a rare day when I spend time at Vauxhall Reef and don’t find “something new” or get an especially good photo of a species I have been chasing for a while.

Today’s (Mar 22, 2024) find was an entirely healthy colony of Pillar Coral (Dendrogyra cylindrus) in the Reef Front zone.

There were a dozen plus healthy colonies of Pillar coral at Vauxhall prior to the arrival of SCTLD in 2023. Pillar coral is considered by AGGRA to be Highly Susceptible to SCTLD, and it seemed odd in early 2023 that these colonies remained healthy while there were seemingly many corals with SCTLD. However, all colonies of Pillar Coral I have seen to date this year (2024)  were entirely or mostly dead. So my secret hope that perhaps the pillar corals at Vauxhall had qualities, e.g. related to their associated microbes, that made them resistant to SCTLD was no more.

But now I can hope that there is something special about this one specimen! I will surely keep an eye on it, also on new growth on colonies killed by SCTLD (see final pic below).

About Pillar Coral

From Cassie Freund 2023 in frostscience.org :

With its tall columns stretching from the seafloor towards the bright sky above, the pillar coral (Dendrogyra cylindrus) is one of the most unique corals in Florida’s waters. Unfortunately, it is also one of the rarest. A new update to the International Union for the Conservation of Nature’s Red List of Threatened Species puts pillar coral on the critically endangered list, just one step below extinct in the wild.

The new Red List classification comes as no surprise to marine biologists, who have been closely monitoring the species for years. Pillar coral has a broad geographic range and can be found in Florida, the Gulf of Mexico, the Bahamas, and throughout the Caribbean. However, the Florida population has drastically declined over the past twelve years due to a combination of warming ocean temperatures (which caused coral bleaching) and the rapid spread of stony coral tissue loss disease. Scientists estimate there are just 40 pillar corals left in the wild in Florida’s waters.

From Wikipedia:

Pillar coral (Dendrogyra cylindrus) is a hard coral (order Scleractinia) found in the western Atlantic Ocean and the Caribbean Sea. It is the only species in the monotypic genus Dendrogyra. It is a digitate coral -that is, it resembles fingers (Latin digites) or a cluster of cigars, growing up from the sea floor without any secondary branching. It is large and can grow on both flat and sloping surfaces at depths down to 20 m (65 ft). It is one of the few types of hard coral in which the polyps can commonly be seen feeding during the day…It usually grows on level or slightly sloping parts of the reef at depths between 1 and 20 metres (3 ft 3 in and 65 ft 7 in)

Pillar coral is a slow-growing, long-lived species. A number of columns grow up from a basal plate; if the whole colony is dislodged and topples over, new cylindrical pillars can grow vertically from the fallen coral. Some specimens have been found where this has happened more than once, and the history of the colony can be deduced from its shape. If a pillar gets detached and becomes lodged in a suitable position, it can continue to live, sending up new pillars from the base and other parts of the column.
Each pillar coral clonal colony is either male or female, an evolutionary life history strategy described as gonochoric. However, hermaphroditic events have been recorded for the species.[6] Sexual reproduction takes place with gametes being released into the water column where fertilisation takes place. The larvae that develop from the eggs are planktonic and drift with the currents before settling on the seabed to found new colonies.

Pics of Pillar Coral on Vauxhall Reef
Click on images for larger versions

On Vauxhall Reef Apr 5, 2019

Vauxhall Reef Apr 12, 2015

Vauxhall Reef, Jan 24, 2015

Vauxhall Reef Feb 8, 2023

Vauxhall Reef Jan 29, 2023

Vauxhall Reef Feb 24, 2024. note there are several living tips of branches!

More Links

Pillar Coral Proposed for Increased Endangered Species Act Protection
Center for Biological Diversity Aug 28, 2023 ” The National Marine Fisheries Service proposed today to change the status of the pillar coral, a species found in Florida waters and elsewhere in the Caribbean, from threatened to endangered under the Endangered Species Act. The proposal is based on population declines and susceptibility to a recently emerged coral disease, according to the Service.”

Researchers Stop Tissue Loss Disease in Rescued Pillar Coral
NCCOS, 03/01/2021 “Based on their trials of different treatments, the team developed a topical antibiotic-infused paste that can be applied directly to SCTLD lesions in aquarium settings to arrest tissue loss and prevent coral death. Treatment methods and results are available in a new publication.